Chengdu Lanzhou railway is another “heavenly road” built on the plateau above 3000 meters above sea level in China
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It is also a major railway channel connecting Sichuan with Northwest China
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It will end the history that there is no railway on the plateau in Northwest Sichuan
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If the construction of Chengdu Lanzhou railway is a tough battle, the connection operation of yuntunpu tunnel is a key battle related to the success or failure of the war Yuntunpu tunnel is located in Songpan County, with a total length of 22.923km
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It is the longest double track tunnel under construction in Asia
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It is a key and difficult control project of Chengdu Lanzhou railway
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The entrance section of the tunnel, which is constructed by China Railway Erju, is 11122m long (accounting for 48.5% of the total length of the tunnel)
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Four cross tunnels and eight working faces are set up for construction, including the No.4 cross tunnel work area One disaster prevention and rescue station
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The plan of the entrance of yuntunpu tunnel and the cross section of yuntunpu tunnel 1 # – 2 #, which was successfully completed at 7:48 on October 14, 2017, are the cross section of the first section of the whole tunnel
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The 1 # – 2 # – transverse tunnel section of yuntunpu tunnel of Chengdu Lanzhou railway is smoothly connected, which provides important technical support for overcoming the worldwide technical problems of complex geological surrounding rock and lays a solid foundation for realizing the whole tunnel connection
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Worldwide technical problems of surrounding rock with complex geology? The problem of large deformation of soft rock has been put forward as a worldwide problem since the 1960s
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In the construction process of underground engineering, the problem of soft rock has always been one of the major problems that perplex the construction and operation of the project
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In the process of building the Chengdu Lanzhou railway, China Railway Erju encountered this world-class problem
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The large deformation sections are concentrated in the work areas of No
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3 and No
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4 Cross Tunnels of yuntunpu tunnel Let’s take a look at the geological conditions of yuntunpu tunnel through the video
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The tunnel is quite sour and cool
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Let’s have a brief experience
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The tunnel area is located between Daxing Township and Songpan County in Songpan County, in the middle of Minshan mountains, on the eastern edge of the Qinghai Tibet Plateau
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There are obvious differences between the East and the west, mainly high mountains
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The rock stratum that the tunnel body passes through is sandstone, slate, limestone, (carbonaceous) phyllite and its interbedding; the rock mass is slightly weathered to strongly weathered, relatively broken to broken, and the uniaxial saturated compressive strength of carbonaceous phyllite is generally less than 5MPa
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The tunnel is located on the right side of the Minjiang River (fault) and is arranged in the north-south direction
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The tunnel area is located in the topographic abrupt change zone of the Sichuan Basin and the east side of the Qinghai Tibet Plateau
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The geological structure belongs to the “a” shaped structure in Northwest Sichuan composed of the Longmenshan fold fault zone, the West Qinling fold fault zone and the Minjiang River fault zone
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The stratum through which yuntunpu tunnel passes has the typical geological characteristics of “four poles, three heights and five complexities”
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@ @ @ @ the accumulation of various unfavorable factors leads to the “world-class” tunnel construction problem of yuntunpu tunnel – large deformation of soft rock, possible deformation of main tunnel and 9052m long large deformation section, accounting for 81% of the total length of pipe section
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Let’s feel the impact of large deformation
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When “Asia’s most” meets “world problem”, how can we deal with it? On July 28, 2016, under the leadership of engineering management center of China Railway Corporation, Chengdu Lanzhou construction headquarters organized domestic well-known experts to survey the site and held the “expert seminar on technical scheme of unfavorable geological engineering of yuntunpu tunnel of Chengdu Lanzhou Railway”, forming the “expert discussion opinions on technical scheme of unfavorable geological engineering of yuntunpu tunnel of Chengdu Lanzhou Railway”
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After the expert seminar on the technical scheme of unfavorable geological engineering of yuntunpu tunnel, the engineering headquarters of Chengdu Lanzhou Railway of China Railway Erju held the “construction work deployment meeting of pilot section” to carry out technical disclosure, training and deployment for the construction of large deformation pilot section
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The key technical achievements of China Railway Erju in the construction of the pilot section of yuntunpu tunnel were praised by CCTV
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Let’s take a look at the yuntunpu tunnel through the video
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After a large number of “Transformers” successively entered the tunnel, they turned into “domestic tunnel mechanized construction vanguard” in one second
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Now let’s feel how these “Transformers” control large deformation of soft rock Hand No.5 waterproof board and steel bar installation two in one platform No.6 self propelled inverted arch mobile trestle No.7 window layer by layer distribution system No.8 belt formwork grouting system No.9 gantry self propelled groove mobile formwork No.10 water stop hot melt welding machine No.11 positioning fixture of low sidewall steel bar water stop No.12 lining maintenance fog gun system after unremitting efforts, large deformation of soft rock tunnel is effectively controlled By September 12, the excavation and support of yuntunpu tunnel project of Chenglan headquarters of China Railway Erju was 9011m, accounting for 80% of the total project
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Can you sweep the world without sweeping a yard? Stamp“
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